I recently went through a successful setup of my Zigbee network, and I’d love to share my experience in case it helps anyone else! 
I started with a Conbee II USB stick and a few Aqara door sensors. Setting them up was a breeze, and the reliability has been fantastic. However, I had two sensors in my garage that kept dropping off the network. After some research, I realized I needed a range extender. I went with a Zigbee-to-WiFi repeater, and it made a world of difference! Now, all my devices stay connected consistently. 
For anyone looking to expand their Zigbee network, I highly recommend checking your device placement and considering a repeater if you have dead zones. It’s amazing how a little tweak can make everything work seamlessly! 
If you have any questions or tips about Zigbee setups, feel free to drop them here—I’d love to chat! 